1. Citrus Fruits

The fact that citrus fruits contain large amounts of Vitamin C is something that is known by most people. It increases the production of white blood cells, which helps fight infections. You see people turning to them after they fall ill, but it’s important to make it a part of your daily diet. And with so many types of citrus fruit available (lemons, limes, oranges, grapefruit, clementine, etc.), that shouldn’t difficult at all!